Articulated crane

ABSTRACT

An articulated crane is disclosed herein having a turntable base pivotally and rotatably supporting an expandable boom. The boom comprises four beams pivotally connected together substantially at their adjacent ends and adapted to be folded together in a compact storage position and to be extended outwardly from the base so that its free end is cantilevered away from said base. The boom further includes crossover braces pivotally secured between the two innermost beams and the two outermost beams so as to provide a scissorslike extension and retraction of the beams. Hydraulic piston and cylinder assemblages are pivotally interconnected between the base and the first beam of the plurality for effecting initial extension of the boom while a second piston and cylinder assemblage effects refined positioning and extension of the boom via the scissorslike mechanism. Means are operably carried on the extreme free end of the boom for engaging cargo or products intended to be lifted or transferred from one location to another.

United States Patent Doyle L. Madole 9948 Glenoaks, Los Angeles County, Calif.

[72] Inventor 91352 [21] Appl. No. 805,444 [22] Filed Mar. 10,1969 [45] Patented Jan. 26, 1971 [54] ARTICULATED CRANE [56] References Cited UNITED STATES PATENTS 2,831,589 4/1958 Way 212/66 Primary Examiner-Harvey C. Hornsby Attorney-Roger A. Marrs ABSTRACT: An articulated crane is disclosed herein having a turntable base pivotally and rotatably supporting an expandable boom. The boom comprises four beams pivotally connected together substantially at their adjacent ends and adapted to be folded together in a compact storage position and to be extended outwardly from the base so that its free end is cantilevered away from said base. The boom further includes crossover braces pivotally secured between the two innermost beams and the two outermost beams so as to provide a scissorslike extension and retraction of the beams. Hydraulic piston and cylinder assemblages are pivotally interconnected between the base and the first beam of the plurality for effecting initial extension of the boom while a second piston and cylinder assemblage effects refined positioning and extension of the boom via the scissorslike mechanism. Means are operably carried on the extreme free end of the boom for engaging cargo or products intended to be lifted or transferred from one location to another.

ATENTEU JAN26 197i 0on5 A. MADOLLC INVISNIOR.

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BY QA PATENTED JANZB I971 V 3.557.967 SHEET h 0F 4 Don. 5 L. M40045 mv/w/ M.

ARTICULATED CRANE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to an articulated crane and, more particularly, to a novel crane having an extendable boom pivotally and rotatably supported on a turntable base adapted to be moved between a compact storage position and an operating position whereby actuation and manipulation of the boom may be effected by a sole operator.

2. Description of the Prior Art Extendable cranes have been employed in the past for lifting and transferring cargo and other objects from one place to another which incorporate a retractable boom. However, problems and difficulties have been encountered when using such conventional equipment in that the crane is bulky and does not lend itself to compact storage for ready mobility. Generally, the boom of the crane comprises a first beam pivotally carried on a mobile base such as a tractor, and a second beam pivotally carried on the cantilevered end of the first beam. Powered cables or hydraulic means interconnect the beams so that they are controllably manipulated so as to maneuver a work gripping device, basket, drill or other work performing implement into a working position.

Normally, one crane operator is required to command the controls for maneuvering while an assistant is required to handle and direct the work implement. Inasmuch as the boom can only pivot at two locations, full articulation cannot be achieved with the result that a predetermined order of work performance must be planned and followed. For example, in performing baled hay stacking or loading and unloading procedures, the placement of individual bales must be programmed because the crane boom cannot attach to selected bales on the far side of a stack without encountering interference with the bales stacked inbetween.

Furthermore, it is highly desirable to mount the crane on a mobile carrier as an accessory for loading and unloading cargo from the carrier. It is common practice to transport hay bales by means of a platform trailer coupled to a powered cab. In some instances, a platform immediately behind the cab is also used to carry the cargo. A longstanding need has existed for the provision of a crane adapted to be mounted on either the cab platform or the platform trailer which is compact for storage and travel purposes and yet fully expandable for reaching and lifting selected cargo carried on the vehicle.

SUMMARY OF THE INVENTION Accordingly, the difficulties and problems encountered with conventional cranes are obviated by the present invention which provides a rotatable turntable base pivotally supporting an expandable, articulated boom comprising a plurality of beams pivotally connected together in substantially endto-end relationship. A scissorslike arrangement of braces is pivotally interconnected at the opposite ends of the braces to selected ones of the beams operable to controllably effect expansion and retraction of the outermost beam via the remaining beams of the plurality. Cargo carrying means are pivotally carried on the extreme end of the outermost beam adapted to grip or otherwise hold a variety of objects, products or the like intended to be moved from one place to the other. Means are coupled between the base and the innermost beam for pivotally displacing the boom outwardly from the-base into a cantilevered position while separate means are coupled between the innermost beam and the next succeeding beam for effecting expansion and retraction of the cantilevered beams via the scissorslike arrangement of braces.

A feature of the invention resides in mounting the base on a mobile vehicle intended to carry the cargo so that the articuiated boom may be employed to load and unload the cargo on and off the vehicle.

Therefore, it is among the primary objects of the present invention to provide a novel crane having automatic control of extension and retraction of an articulated boom for effecting the transfer of cargo from one place to another.

Another object of the present invention is to provide a novel articulated boom for a mobile crane adapted to rotate about a vertical axis and to retractably extend in a cantilevered manner outwardly from a supporting base.

Still another object of the present invention is to provide a novel crane having an expandable boom including separate control means for effecting rotation of the boom, extension of the boom and positioning of a cargo carrying means carried on the end of the boom.

A further object of the invention resides in providing a crane having a plurality of pivotally connected beams adapted to be expanded and retracted via a scissors brace arrangement actuated by hydraulic piston and cylinder assemblages.

Still a further object of the invention provides a novel crane operable by a sole operator and which may be carried on a cargo platform of a vehicle intended to transport the cargo.

BRIEF DESCRIPTION OF THE DRAWINGS The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation, together with further objects and advantages thereof, may best be understood by reference to the following description. taken in connection with the accompanying drawings in which:

- FIG. 1 is a side elevational view of a novel articulated crane illustrating the expandable boom in its compact folded position;

FIG. 2 is an enlarged side elevational view of the extreme end of the boom showing a cargo gripping means carried thereon;

FIG. 3 is a plan view of the gripping means as taken in the direction of arrows 3-3 of FIG. 2;

FIG. 4 is a rear elevational view of the articulated crane shown in FIG. 1 as taken in the direction of arrows 4-4 thereof;

FIG. 5 is an enlarged elevational view of the turntable base supporting the expandable boom;

FIG. 6 is a sectional view as taken in the direction of arrows 6-6 of FIG. 1 showing the turntable base in plan view;

FIG. 7 is a side elevational view of the articulated crane showing the expandable boom partially extended from the turntable base; and

FIG. 8 is a side elevational view of the articulated crane showing the boom expanded and in a cargo engaging position in broken lines, and in a cargo transferring or lifting position in solid lines.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, the novel crane of the present invention is illustrated in the general direction of arrow 10 which includes an annular base 11 from which an articulated boom indicated by arrow 12 expands and retracts under the control of actuating means taking the form of piston and cylinder assemblages l3 and 14, respectively. The base II rotatably supports a turntable or platform comprising parallel vertical plates 15 and 16 and platform sections 17 and 18 as seen in FIG. 6. Plates l5 and 16 are rotatably supported on a track 20 formed on the top of base 11 by rollers 21 and 22. The extreme ends of platform members 17 and 18 include rollers 23 and 24 which rollably engage the underside of the track 20. Additionally, plates 15 and 16 further include a downwardly depending roller 25 which rides on the underside of track 20 in a similar fashion to the rollers 23 and 24. In this manner, the turntable arrangement is rotatably mounted on the base 11 which is adapted to rotate about a vertical axis.

As shown in FIG. 5, the turntable is ,driven by a motor 26 having a drive shaft terminating in a pinion gear 27 meshed with the inside diameter teeth of a ring gear 28. The ring gear is fixed on the inside of the base 11 sidewall.

Referring to FIG. 4, the ends of platform members 17 and 18 pivotally mount the legs 30 and 31 of a yoke via supports 32 and 33 and pivot connections 34 and 35. The opposing ends of legs 30 and 31 are fixedly secured to the opposite sides of a main beam 36 of the boom 12. The end of beam 36 is pivotally connected between the plates and 16 by means of a pivot 37.

With reference to FIG. 5, it can be seen that the plates 15 and 16 are joined together by a cross support 38 which is carried on a mount 40 coaxially disposed with respect to the ring gear 28 and the annular sidewall of the base 1 1. The mount 40 rests on a bearing assembly 41 so that an axle 42 may be free to rotate about a vertical axis. In this manner, the boom assembly mounted on the plates 15 and 16 may be rotated about the stationary base 11.

Referring more particularly to FIG. 7, it can be seen that the boom primarily comprises the main beam 36 pivoted at one end to the turntable platform and pivotally connected at pivot 43 to a second beam 44 which in turn is pivotally mounted to the end of a third beam 45 via pivot 46. The opposite end of beam 45 is pivotally connected to an outermost beam 47 via pivot connection 48. As illustrated, the main or innermost beam 36 is in an upright vertical orientation while the beams 44, 45 and 47 are expanded about the pivot connections 43, 46 and 48 respectively. It is to be noted that the adjacent ends of beams 44 and 45 are connected together by pivot 46 while the pivot connections 43 and 48 connect to beams 44 and 47 a slight distance from the extreme terminating end of each beam. The beam section between pivot 48 and the end of beam 47 is indicated by numeral 50 while the beam segment of beam 44 extending between the pivot 43 in the extreme terminating end thereof is indicated by, numeral 51. It is also to be noted that beam segment 51 is formed at an angle to the major longitudinal axis of the beam 44.

Expansion of beams 44, 45 and 47 with respect to the main beam 36 is effected via a scissorslike arrangement comprising a pair of braces 52 and 53 which cross over upon themselves and are pivotally attached to the beams. Brace 52 is attached to the extreme end of main beam 31 by pivot connection 54 while its opposite end is connected to beam 45 via pivot connection 55. The ends of brace 53 are connected to the extreme end of beam 47 via pivot connection 56 while its opposite end is pivotally connected to beam 44 via pivot connection 57. It is to be noted that the beam segment between pivot connection 55 and the end of beam 45 is indicated by numeral 58 while the beam segment of beam 44 between pivot connection 57 and the extreme end thereof is indicated by numeral 60. Furthermore, the beam segment between pivot 43 and the extreme end of main beam 31 to which brace 52 is attached via pivot connection 54 is indicated by numeral 61. To assure that the boom is fully articulated, it is to be noted that the beam segment 62 of beam 45 is angularly displaced with respect to the longitudinal axis of the beam, and that pivots 46, 55 and 56 are offset from the major longitudinal beam axis.

Therefore, it can be seen that the boom will be fully articulated upon the movement of beam segment 51 on pivot 43 so that beams 45 and 47 will pivot about connections 46 and 48, respectively. The braces 52 and 53 will maintain stability of the boom during expansion and the crossover point of the braces will change as the two midsection beams 44 and 45, as well as the outermost beam 47, expand. As the beam segment 51 is moved upwardly at its extreme end, the boom will move toward the main beam 36 and assume a collapsed or stored position such as is shown in FIG. 1. However, if the free end of beam segment 51 is moved downwardly about the pivot 43, the articulated beam will extend outwardly as shown in FIG. 8. To move the beam segment 51 and hence beams 44, 45 and 47, a piston and cylinder assemblage 14 is employed.

The cylinder of the assemblage is pivotally connected to the main beam 36 midway between its opposite ends by a pivot connection 63 while the free end of the piston of the assemblage is pivotally connected to the beam segment 51 via pivot connection 64. Therefore, it can be seen that hydraulic actuation of the piston and cylinder assemblage 14 will readily move the beam 44 about pivot connection 43 to expand or retract the respective beams as stabilized by the scissorlike braces 52 and 53.

Beams 44, 45 and 47 may be moved outwardly as a unit by pivotal positioning of the main beam 36 via piston and cylinder assemblage 13. The end of the cylinder is pivotally connected to the main beam 36 by a pivot connection 65 suitably secured on a support mount 66 braced by support mount members 67 and 68 so as to be positioned to the rear of the main beam 31 and disposed between the pivot connection 63 and the pivot connection 43. The piston and assemblages 13 and 14 are suitably coupled to conventional reservoir and pump equipment (not shown) so that actuation thereof may be achieved automatically via pushbutton operation by the operator.

It is also to be noted that although a single illustration of each beam is shown in FIG. 7 in side elevation,'it is to be understood that each of the beams and braces are duplicated on the opposite side such as is partially shown in FIG. 4 by identical numerals employing prime indicators.

Referring now to FIGS. 2 and 3 in detail, it can be seen that the extreme end of the boom 12 carries a cargo gripping or holding means indicated in the direction of arrow 70. Specifically, the extreme free end of beam 47 is pivotally attached to an extension beam 71 via a pivot connection 72. The extension beam 71 is pivoted by means of a bellcrank 73 pivotally carried on the beam 47 via pivot connection 74 wherein one end of the bellcrank is pivotally secured to one end of a link 75 while its opposite end is pivotally connected to the extension beam 71. Positioning of the extension beam is achieved by a piston and cylinder assemblage 76 pivotally connected between beam 47 and the other end of the bellcrank 73at pivot connection 77.

The end of extension beam 71 opposite to its end pivotally carried on beam 47 carries a gripping means comprising opposing jaw sets 78 and 80 pivotally carried on a block 81. Each jaw set includes a hook member disposed on opposite sides of the block 81 and rotatably mounted thereon via shafts 82 and 83 as seen in FIG. 3. The jaw sets are rotated toward and away from each other by means of a piston and cylinder assemblage 84 which is carried at one end by the block and which is connected to shaft 82 via a connecting link 85. When actuated, shaft 82 will rotate and its rotational movement is translated into rotational movement of shaft 83 via meshed gears 86 and 87. The cargo engaging head or gripping means 70 may be rotated by rotatably mounting the block 81 to the end of extension beam 71 via a bearing mount and shaft arrangement 88 which includes a pulley wheel 90 driven by a motor 91 via a pulley belt 92.

It is to be understood that although a gripping means is illustrated, other forms of cargo engaging, holding or retaining means may be employed. Also, the present invention encompasses the placement of a personnel carrying basket or cage on the end of extension beam 71 in the event it is desired to move and support personnel on the end of the crane boom.

Referring now to FIG. 8, it can be seen that the novel crane having an extendable and retractable articulated boom may be readily carried on a cargo platform 95 forming a part of a mobile vehicle or carrier supported on wheels 96. Preferably, the base 11 is disposed substantially in the center of the platform between the end thereof and a driver's cab '97 so that cargo may be stored ahead of and behind the crane. It is customary when employing this type of vehicle to include a platform trailer (not shown) which is detachably connected to the cargo platform 95 on which the bulk of the cargo is stored for transportation. As illustrated, the cargo takes the form of hay bales 97 which are initially stacked on the ground awaiting transfer to the mobile vehicle. The crane may be operated by a single operator having a suitable console connected to conventional hydraulic pumps and reservoirs that are operably connected to the plurality of piston and cylinder assemblages. The crane may be employed to load the bales of hay onto the platform trailer and the platform 95. After the vehicle has transported the cargo to its destination, the crane can again be used to unload the cargo from the vehicle. During transportation, the crane may be manipulated to its storage position, such as is shown in FIG. 1, where a minimum volumetric area is occupied by the equipment.

As shown in broken lines, the main beam 36 has been pivoted on the turntable base so that the gripping jaws may engage with a selected bale of the stack. To achieve such engagement, the various piston and cylinder assemblages may be selectively actuated independent of each other to extend the boom 12, position the extension beam 71, rotate the block 81 and to actuate the gripping means 70. As shown in solid lines, the main beam 36 is rotated rearwardly on its pivot by means of piston and cylinder assemblage 13 which causes the selected cargo engaged by the gripping means to be lifted and therefore separated from the stack.

Therefore, it can be seen that the novel crane having an articulated boom is an advancement in the state of the art and that the objects of the present invention are fully met. The

crane is mobile and may be carried on the cargo platform on which the cargo is to be loaded and unloaded by the crane. The boom, as well as the gripping means, are selectively operable so as to achieve various manipulations and maneuvers to locate the gripping means in a desired location.

While particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects, and, therefore, the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

lclaim:

l. A mobile crane comprising:

a base;

a turntable rotatably carried on said base;

an articulated boom pivotally carried on said turntable;

said boom comprising a main beam pivoted on one end to said turntable;

a plurality of beams pivotally connected together in substantially end-to end relationship and pivotally connected to said main beam so as to be retractably extended outwardly therefrom;

a scissorlike arrangement of braces crossing over each other and pivotally connected at their extreme ends to selected ones of said plurality of beams and wherein a selected one of said braces in said arrangement is pivotally connected to the end of said main beam opposite to its end pivotally connected to said turntable; and

means operably connected between said turntable and said main beam and between said main beam and a selected one of said plurality of beams for pivoting said main beam and for extending and retracting said plurality of beams.

2. The invention as defined in claim 1 wherein said operable means includes a pair of piston and cylinder assemblages, one of said pair pivotally connected between said turntable and said main beam and the other one of said pair pivotally connected between said main beam and the end of said beam pivotally connected to said main beam.

3. The invention as defined in claim 2 wherein the outermost beam of said plurality includes a cargo transferring means pivotally and rotatably carried thereon.

4. The invention as defined in claim 3 including a piston and cylinder assemblage pivotally connected between said outermost beam and said transferring means for selectively pivoting said transferring means.

" 5. The invention as defined in claim {wherein said plurality of beams comprises four elongated beams, the innermost pair of said beams pivotally connected at their adjacent ends and including a beam segment integrally formed at the opposite end of each innermost beam angularly disposed with respect to the major axis of each of said innermost beams.

6. The invention as defined in claim 5 wherein said operable means includes a piston and cylinder assemblage pivotally coupled between the midsectior of said main beam and the end of said beam segment associated with the first innermost beam of said pair and a second piston and cylinder assemblage pivotally coupled between said turntable and said main beam.

7. The invention as defined in claim 6 including:

a cargo engaging and holding means carried of the extreme end of the outermost beam of said plurality;

pivotal means mounting said cargo engaging and holding means on said outermost beam; and

rotatable means rotatably mounting said cargo engaging and holding means on said outermost beam.

8. The invention as defined in claim 7 wherein said cargo engaging and holding means includes a pair of jaw members adapted to converge to engage cargo.

9. The invention as defined in claim 1 including:

a mobile vehicle having a cargo platform; and

said base mounted on said platform so that said boom is operated therefrom to effect loading and unloading of cargo on and from said platform. 

1. A mobile crane comprising: a base; a turntable rotatably carried on said base; an articulated boom pivotally carried on said turntable; said boom comprising a main beam pivoted on one end to said turntable; a plurality of beams pivotally connected together in substantially end-to-end relationship and pivotally connected to said main beam so as to be retractably extended outwardly therefrom; a scissorlike arrangement oF braces crossing over each other and pivotally connected at their extreme ends to selected ones of said plurality of beams and wherein a selected one of said braces in said arrangement is pivotally connected to the end of said main beam opposite to its end pivotally connected to said turntable; and means operably connected between said turntable and said main beam and between said main beam and a selected one of said plurality of beams for pivoting said main beam and for extending and retracting said plurality of beams.
 2. The invention as defined in claim 1 wherein said operable means includes a pair of piston and cylinder assemblages, one of said pair pivotally connected between said turntable and said main beam and the other one of said pair pivotally connected between said main beam and the end of said beam pivotally connected to said main beam.
 3. The invention as defined in claim 2 wherein the outermost beam of said plurality includes a cargo transferring means pivotally and rotatably carried thereon.
 4. The invention as defined in claim 3 including a piston and cylinder assemblage pivotally connected between said outermost beam and said transferring means for selectively pivoting said transferring means.
 5. The invention as defined in claim 1 wherein said plurality of beams comprises four elongated beams, the innermost pair of said beams pivotally connected at their adjacent ends and including a beam segment integrally formed at the opposite end of each innermost beam angularly disposed with respect to the major axis of each of said innermost beams.
 6. The invention as defined in claim 5 wherein said operable means includes a piston and cylinder assemblage pivotally coupled between the midsection of said main beam and the end of said beam segment associated with the first innermost beam of said pair and a second piston and cylinder assemblage pivotally coupled between said turntable and said main beam.
 7. The invention as defined in claim 6 including: a cargo engaging and holding means carried of the extreme end of the outermost beam of said plurality; pivotal means mounting said cargo engaging and holding means on said outermost beam; and rotatable means rotatably mounting said cargo engaging and holding means on said outermost beam.
 8. The invention as defined in claim 7 wherein said cargo engaging and holding means includes a pair of jaw members adapted to converge to engage cargo.
 9. The invention as defined in claim 1 including: a mobile vehicle having a cargo platform; and said base mounted on said platform so that said boom is operated therefrom to effect loading and unloading of cargo on and from said platform. 